A metre scale made of steel is calibrated at 20 degrees Celsius to give correct reading. Find the distance between 50cm mark and 51cm mark if the scale is used at 10 degrees Celsius. Coefficient of linear expansion of steel is 1.1 x 10-5 C-1
The answer given is 1.00011cm
Logically, it is incorrect as steel contracts on cooling. So distance between any two consecutive marks should be less than 1cm. Am I right?
71No, the answer given is right.
What you have missed actually that say-
Reading -> | |
50 51
Scale -> ------------
Let these be two marks @ 20C. Now since the scale has contracted, it would measure less than actually it does i.e, 1cm, as a result of which if we measure the same distance of 1cm (which the scale could measure earlier) with contacted scale, It would be higher than 1 cm.
1I understand what you are talking about.
The question does not say ' If we measure the original 1 cm distance with contracted scale, what will be the distance'
It just says what is the new distance b/w 50cm and 51cm mark. Earlier it was 1 cm....when it got contracted, the distance decreased. As simple as that!
